Fuel injection nozzle with heated valve

Abstract

A fuel injection nozzle with heated valve for flash boiling of fuel during injection includes a nozzle body of electrical conductive material with a spring biased valve of electrical conductive material operatively positioned in an axial extending fuel passage within the nozzle body so as to control the flow of fuel out through a discharge outlet at one end of the nozzle body. An electrical insulator sleeve encircles and is fixed to the valve intermediate the ends thereof so as to support a coiled electrical heater wire that is connected at one end to the valve adjacent to its tip end and which is connected at its opposite end to an electrical conductor sleeve that is fixed to the insulator sleeve. An electrical brush device is operatively associated with the nozzle body so that one end thereof is in sliding electrical contact with the conductor sleeve while its opposite end is connectable to a source of electrical power whereby an electrical current can be supplied to the heater wire to effect heating of fuel in the fuel passage prior to its discharge from the nozzle.

The embodiments of this invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A fuel injection nozzle for use to effect flash injection of fuel, said nozzle including a nozzle body means of electrical conductive material having a spray outlet orifice means at one end thereof and a fuel passage means connectable at one end to a source of pressurized fuel, said fuel passage means at its other end being in communication with said spray outlet orifice means and having a valve seat upstream of said spray outlet orifice means, a valve of electrical conductive material operably positioned in said fuel passage means for movement into and out of engagement with said valve seat, a spring means operatively associated with said valve to normally bias it into engagement with said valve seat; an electrical heater means operatively associated with said valve in a position to effect heating of fuel within said fuel passage means and, an electrical connector means operably positioned in said nozzle body means with one end thereof in operable contact with said heater means and with its other end being connectable to a source of electrical power whereby an electrical current can be caused to flow through said heater means to effect heating of fuel in said passage means whereby to provide for the flash-injection of fuel during opening movement of said valve. 
     
     
       2. A fuel injection nozzle for use to effect flash injection of fuel, said nozzle including a nozzle body means of electrical conductive material having an outlet at one end thereof and a fuel passage means connectable at one end to a source of pressurized fuel and in communication at its other end with said outlet and having a valve seat encircling said outlet, a valve of electrical conductive material operably positioned in said fuel passage means for movement into and out of engagement with said valve seat, a spring means operatively associated with said valve to normally bias it into engagement with said valve seat, an electrical insulator means encircling said valve intermediate its ends, an annular electrical conductor fixed to and encircling one end of said insulator means, an electrical heater means wound on said insulator means and operatively connected at one end to said conductor and at its other end to said valve and, an electrical brush means operably positioned in said nozzle body means with one end thereof in sliding contact with said conductor and its other end being connectable to a source of electrical power whereby an electrical current can be caused to flow through said heater means to effect heating of fuel in said passage means whereby to provide for the flash-injection of fuel during opening movement of said valve. 
     
     
       3. A fuel injection nozzle with internal heater, said nozzle including a nozzle body means of electrical conductive material having a spray outlet at one end thereof and a fuel passage means connectable at one end to a source of pressurized fuel and in communication at its other end with said spray outlet and having a valve seat encircling said spray outlet, a valve of electrical conductive material operably positioned in said fuel passage means for movement into and out of engagement with said valve seat, a spring means operatively associated with said valve to normally bias said valve into engagement with said valve seat, an electrical insulator means fixed to and encircling said valve intermediate its ends, an annular electrical conductor fixed to one end of said insulator means, an electrical heater means wound on said insulator means and connected at one end to said conductor and at its other end to said valve and, an electrical brush means operably positioned in said nozzle body means with one end thereof in sliding contact with said conductor and its other end being connectable to a source of electrical power whereby an electrical current can be caused to flow through said heater means to effect heating of fuel in said passage means close to said spray outlet whereby to provide for the flash-injection of fuel during opening movement of said valve.